Boosted by higher fuel costs, imports rose 16 percent from a year earlier to 6.74 trillion yen ($68.7 billion) while exports climbed 14.7 percent to 5.78 trillion yen ($58.9 billion). The deficit was a quarter bigger than the 768.4 billion yen gap seen in August 2012.

Japan’s trade accounts fell into deficit as costs for importing crude oil and natural gas soared following the closure of nuclear plants after the March 2011 earthquake and tsunami on its northeastern coast led to meltdowns at the Fukushima Dai-ichi plant.

Costs of imported fuel, which comprise more than a third of all imports, rose nearly 18 percent in August, despite a slight decline in volume.

The value of total imports of food, raw materials and manufactured goods also rose at a double-digit pace from the same month a year earlier, while import volumes of most declined.

Ultra-easy monetary policy has weakened the yen, boosting exports, but the increase has not been enough to offset surging import costs.

Economists had forecast the deficit at around 600 billion yen for August.

Japan’s exports to the rest of Asia, North America and the European Union have rebounded in recent months, as recoveries in many markets have gained momentum. Exports to the U.S. jumped nearly 21 percent in August from a year earlier, while imports rose 14 percent, leaving a surplus of 495.3 billion yen ($5 billion).

But Japan runs deficits with many of its biggest trading partners, including China. Exports to mainland China rose about 16 percent year-on-year in August to 1.1 trillion yen ($11.2 billion) while imports jumped almost 18 percent to 1.4 trillion yen ($14.5 billion).